Middleware that uses the authentication handler

auth-middleware.ts

import { NextFunction, Request, Response, RequestHandler } from 'express';
import HttpException from '../model/HttpException'
import { isAuthorized } from '../utils/auth-utils'
import { aliasExists } from '../accessor/database.mongo'

export function authorizationMiddleware(): RequestHandler {
    return async (
        request: Request,
        response: Response,
        next: NextFunction) => {

        // Check if user is even signed in.
        if (!request.cookies.jwt) {
            next(new HttpException(401, "Authentication required"))
        }

        // Get necessary alias from user param.
        const user = request.params.user

        // Check if user even exists.
        if (!aliasExists(user)) {
            next(new HttpException(404, `User "${user}" not found.`))
        }

        // Authenticate request.
        const isAuth = await isAuthorized(request, user)
        console.assert(isAuth, `User "${user}" is unauthorized!`)
        if (!isAuth) {
            next(new HttpException(403, "Forbidden request"))
        } else {
            console.log(`User "${user}" is authorized!`)
            next()
        }
    }
}